bush unleashed what later became known as shock and awe. a massive aerial assault that lit up the night sky in baghdad. we were told it would be a quick war. it was about finding and stopping weapons of mass destruction and we would be greeted as liberators. that did not turn out to be the case. now a decade later in our latest poll, a clear majority of americans say the iraq war was not worth it -- the cost in american lives or dollars. our chief foreign correspondent richard engel spent the better part of the last decade covering the war. he has our report tonight. >> reporter: today, baghdad looked like the place many american troops will remember. more than a dozen bombings, dozens dead. ten years after president bush launched shock and awe and toppled saddam hussein, the iraq war has started again. sunnis versus shiites. it's their fight now. but both sides blame the united states for blundering in, looking for weapons of mass destruction that weren't there, undoing iraq's delicate religious balance. hardly the stability desired after